Peel and cut the Starchy Potatoes into even chunks, place them in a pot and cover with cold Water; add a generous pinch of Salt, bring to a boil, then simmer until the potatoes are very tender, about 15–20 minutes.
Meanwhile, peel, core and dice the Tart Apples. Put them into a small saucepan with a couple of tablespoons of Sugar and a splash of Water and cook over medium heat until the apples break down and are soft, about 8–10 minutes. Mash lightly or puree to your desired texture and keep warm.
Drain the potatoes well, return them to the pot off the heat and mash. Warm the Whole Milk gently and mix into the potatoes with a tablespoon or two of Butter until smooth and creamy. Season with more Salt to taste and a grating of Nutmeg for warmth.
While the mash rests, thinly slice the Onions. Heat a couple of tablespoons of Clarified Butter in a skillet and cook the onions over medium-low heat, stirring occasionally, until they are deep golden and caramelized, 10–15 minutes. Set aside.
In a separate pan, slice the Blood Sausage into rounds and fry them gently until the edges are crisp and the centers are heated through, 3–5 minutes per side. Season lightly with freshly ground Black Pepper.
To serve, spoon the mashed potatoes onto plates, add a generous portion of the stewed apples alongside (or a scoop on top if you prefer), arrange the fried blood sausage slices over or beside the mash, and finish with a scattering of caramelized onions. Adjust seasoning if needed and enjoy hot.
